1. Cut up pretzels. Set aside.
2. In large sauté pan, cook onion, garlic, and celery until soft and translucent.
3. Add sausage and cook until fully cooked through.
4. In a large bowl, whisk together eggs, chicken stock, and melted butter.
5. Add pretzels, onion mix, herbs, salt, and pepper to the bowl, and stir to combine.
6. Put mixture into a buttered 9x9 casserole dish.
7. Bake at 350 for 50-60 minutes, until golden brown on top, and the center springs back when gently pressed.

Notes:

For best results, let cut pretzels dry out at room temperature for several hours or overnight.
Stuffing can be made up to two days in advance and stored in the refrigerator overnight.
Before baking, toss ingredients in liquid as it will sink to the bottom.